[Langerhans cell histiocytosis with orbital involvement in an infant: Case report].

The Langerhans cell histiocytosis is a rare disease characterized by the clonal proliferation of CD1a + myeloid dendritic cells associated with a significant inflammatory component. The localized form of the disease is called eosinophilic granuloma. Bone involvement is common; in children, lytic lesions are most frequently found in the cranial dome being rare in the orbit. We present an 18-month-old infant who consulted due to periorbital edema and proptosis of the right eye, with two months of evolution. The computed tomography and the magnetic resonance imaging showed a maxillary sinus tumor mass of expansive growth and erosion of the roof of the orbit. The biopsy confirmed CD1a+ proliferation; it was treated with prednisone and vinblastine with favorable evolution. It is a rare entity that requires a high index of suspicion and multidisciplinary management. Early diagnosis and treatment leads to a favorable prognosis for the patient.